


In Posterum

by orphan_account



Category: Original Work
Genre: Anal Fisting, Daddy Kink, Extremely Underage, F/M, Fisting, Incest, Multi, Parent/Child Incest, Sibling Incest, Slavery, Urethral Play
Language: English
Status: Completed
Published: 2019-02-17
Updated: 2019-02-17
Packaged: 2019-10-30 05:46:02
Rating: Explicit
Warnings: Rape/Non-Con, Underage
Chapters: 1
Words: 2,602
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17823020
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: Set in the future of Concubitus Varii.Hart's son wants a little sister to play with.





	In Posterum

**Author's Note:**

> Set six years after the events in Concubitus Varii.

 

 

 

Ada lay prone on her father’s bed and shrieked in tandem with the thrusts of Stasimus’ tiny fist. The four year old had his whole hand inside of her bladder, ignoring his mother’s cries like usual. He had grown up with her screaming and begging and so her pleas for him to stop only made him widen his hand and wiggle his fingers. The young woman tensed as her son tickled her insides, getting dangerously close to cumming. 

 

The little boy took his other slick fist and lined it up with Ada’s asshole, sinking his hand deep inside of her easily. The young woman let out a long moan and let herself cum as her son double fisted her. 

 

The boy slid his small hand from her bladder, watching her urethra gape open. Thanks to all of the training it had had it would never completely close again. 

 

Hart watched from across the room, seating in a plush armchair. He grinned and clapped for his son, “good job, Stasimus. You made your mommy cum extra hard.”

 

Stasimus puffed up his chest and pulled his other fist from Ada’s ass, “thank you, Father.”

 

Hart had officially made the boy his heir, granting him citizenship as soon as he was born. Despite Ada’s status as a slave the child still came from good breeding, and as he was a boy Hart had made the decision to accept him as his son. 

 

He watched as Stasimus crawled up to his mother’s breast and take a nipple into his mouth. The young woman was dry by now, but the boy continued to suckle on her, still comforted by the tit in his mouth. 

 

He smiled and brought his teeth together slightly just to make his mother jump. He snickered at her little yelp and bit her again before moving his abuse to her other nipple.

 

“Baby, no, please,” Ada begged him as he bit a bruise into her breast. 

 

“No marks,” reminded their father sharply. 

 

Stasimus pulled away with a fierce pout, “yes, Father. She’s prettier unmarked,” he repeated the rule. 

 

“You know,” Hart began with a grin as he moved across the room, “I’ve been thinking about giving you a little sister to play with, would you like that?”

 

Ada froze, the feeling of being doused with cold water washing over her. 

 

“I wanna put the baby in her,” Stasimus demanded his father, his eyes on Ada’s belly. 

 

Hart laughed as he reached the couple lying on the huge bed, “you’re a bit too young for that yet, but perhaps later with your sister.”

 

The little boy nodded, disappointed but accepting, “are you going to make the baby now? Can I help?”

 

“What do you say, Ada, can he help?”

 

“Of course he can help us m-make a baby,” she whispered obediently. 

 

Hart removed his clothes and Ada watched the man fold each article before placing it on his chair. He returned fully nude, his large erection pointing up toward his flat stomach. He held a syringe in his hand and Ada accepted the fertility drug in her arm without a fight, docile. It had been cocktailed to ensure a female pregnancy, Ada knew, and she held back tears at the thought of what her daughter would go through after she was born a slave. 

 

The man got on the bed and knelt. He pulled Ada to him by the hips, sliding her down the sheets until she lay flat on her back with her ass in his lap, her legs splayed. He entered her in one smooth motion, the girl still wet and loose from her recent orgasm. 

 

Ada sighed in pleasure as he sank inside, loving the feeling of a full pussy. 

 

“I can’t wait to see you swollen with child again. Do you remember how horny you got? You begged for sex. You  _ cried _ for it,” Hart reminded her as he snapped his hips forward.

 

“Yes Daddy, I remember that I needed to be fucked so badly.”

 

Ada fisted the sheets under her as Hart changed his angle and began bumping against her G-spot. Stasimus decided to join in the fun, brushing his mother’s fiery red curls off of her breasts almost tenderly. The boy took one of Ada’s breasts in each hand and squeezed, causing the woman to hiss. 

 

“Be nice to your mommy,” Hart scolded, “we’re making a baby right now, we have to be gentle.” 

 

Stasimus let go of Ada’s tits and pouted, “okay, Father.” 

 

He brushed his fingers across the pink nubs of his mother’s nipples, tickling her slightly before he began plucking at the little nubs, watching her chest heave, “I wanna make her cum,” the boy whined. 

 

“So then make her cum,” Hart told his son. 

 

Stasimus reached a hand down between Ada’s legs, trying to keep his hand out of the way of his father’s thrusting cock. He pinched Ada’s clit roughly for a moment, making her cry out and scramble for purchase on the bed, “Stasimus, no!”     

 

He ignored her like always and tugged her clit again, watching her whole body jolt. He moved to gentle ministrations after a look of admonishment from his father, rubbing the nub under his finger back and forth. 

 

Ada moaned and flung a hand above herself in pleasure, “Oh, good boy Stasimus,  _ oh!”  _

 

She came hard, her father still pistoning inside of her and her son not letting go of her clit, “please, that’s enough baby,  _ no!” _

 

A second orgasm was torn from the young woman, and she grabbed at the man above her, placing her hands on his arms\and squeezing. 

 

The man came to the feeling of her gripping onto him with her both hands and pussy. He grunted and shoved himself in as far as he could go, shooting his hot cum against her cervix.

 

“Did we make a baby?” asked Stasimus.

 

“Hopefully. But if we didn’t make a baby this time we’ll just have to keep practicing, won’t we?”

 

“Yes, Father,” the boy reached down and fiddled with one of Ada’s nipples as she lay prone on the bed, “when will I be able to fuck my sister?”

 

Hart let himself smile at the eager boy, “As soon as your little cock gets big enough.”

 

“How long will that be?”

 

“Oh, just a few years,” Hart reassured him, “and you can always play with her until then,” he gestured at Ada.

 

“Will my sister suck my cock like Mommy and Jamie do?”

 

Hart turned to Ada and raised an amused eyebrow.

 

“Yes, your sister will suck your cock just like your aunt and me,” she told the boy. 

 

“Okay,” Stasimus chirped and spread his naked legs, “mommy, suck me, I wanna cum like you and daddy.”

 

Ada obeyed her son and leaned forward in order to take his tiny member into her mouth. She placed a steadying hand on his hip as his hips jerked upward in a thrust and tried not to listen to him moan. She sucked firmly, pausing occasionally to run her tongue over the boy’s dick teasingly. 

 

The boy frowned at her and demanded she suck.

 

He moved his hands to her head and gripped at her curls, tugging cruelly and making Ada wince as she sucked. Stasimus began huffing and jerking, getting close to his orgasm. 

 

Hart watched his daughter give their son head, pleased. It was extremely likely that he had successfully impregnated the young woman, and he imagined her doing this to Stasimus while full of child, leaning her heavy belly down over their son as she sucked him into her mouth.

 

That would be his reality soon enough. 

  
  


\----------------

  
  


Stasimus would not leave his father alone about impregnating his sister. He had chattered about it when he was four and the girl not yet even born, and he insisted on it now that he was eight. 

 

“You’re still too young to put a baby in Annia,” Hart told him for the millionth time. 

 

The man paused and looked the boy over, considering. “You could fuck her though, would you like that?” 

 

He smiled at the boy’s eager nod. 

 

Stasimus was given a pill which he swallowed with distaste. He hadn’t questioned what the pill had been, trusting his father to do what was best for him like always. 

 

His little cock started stiffening as the drugs hit his system, forcing an artificial erection on the boy. It didn’t feel at all unpleasant, and Stasimus tried to reach down between his legs to touch himself. 

 

Hart slapped his hand away, “don’t you want to fuck your sister?”

 

“Yes Father, I wanna fuck her.” 

 

Hart called Ada into the bedroom. 

 

She stepped through the door with Annia in her arms, the three year old sound asleep with her blonde head resting against her mother’s shoulder. 

 

When she saw Stasimus perched on the bed with an erection she held Annia tighter to her breast, “today?” she asked her father shakily. 

 

“Today,” Hart confirmed, “today our children lose their virginities together,” he gently pressed his hand to the side of her face, smoothing her lip with his thumb.

 

She knew better than to argue and gently lay the little girl down on the bed. Annia woke, her blue eyes fluttering open as she took in her surroundings. 

 

“We want Annia to enjoy this, don’t we?” Hart asked his son.

 

“Yes, I want her to cum.” 

 

“Then we should make her feel good, right?”

 

Stasimus nodded in agreement and slipped practiced fingers between his little sister’s legs. He played with Annia like this all the time and was no stranger to making her cum. 

 

The girl quickly began to whimper as her brother slid his small fingers inside of her pussy, curling his fingers to find the girl’s G-spot like he had been taught. 

 

He was a bit over enthusiastic, and Hart had to slow the boy down when the little girl’s hips started twitching. 

 

“No, Stasimus!” Annia protested as the ministrations stopped. 

 

“She’s ready for you to fuck her,” Hart told the boy, hand on his shoulder. 

 

“Oh. Okay,” the eight year old agreed and stepped forward. 

 

He had seen plenty of fucking in his life so he knew how it worked, but he still struggled a bit trying to get his dick inside of Annia’s tight hole.

 

Annia started crying as she was entered, overfull.

 

“ _ Oh wow, _ ” Stasimus breathed as he bottomed out inside of the girl and ignored her whimpers. 

 

She was so warm and soft inside and Stasimus had to hold very still for a moment to keep from cumming right there. Fat tears rolled down Annia’s cheeks and she kicked her little legs out, trying to relieve her discomfort. 

 

Stasimus frowned down at her, “hey, quit it,” he pinched one of the little girl’s nipples in reprimand. 

 

The girl cried harder. 

 

Ada crawled onto the bed and began to stroke the little girl’s golden curls, but the crying didn’t stop. 

 

Annoyed, Stasimus began to fuck her anyway. He wasn’t going to let her spoil this just because she was being a brat. 

 

Annia stiffened as the boy’s dick began moving inside of her, huge in comparison to her tiny pussy.   

 

“No no no!” the little girl wailed. 

 

Ada had to take the girl’s hands and pin them in order to keep her from hitting her brother, “shhh, it’s alright, it will feel good soon,” she soothed her. 

 

Her mother was right, and soon the familiar feeling of arousal returned to her. She wiggled her hips experimentally and sighed. Her brother felt so good inside of her now that she had been loosened a little, and she let out little whines as her brother thrusted into her. 

 

“She feels so good, Father,” Stasimus exclaimed, beginning to slam himself into the little girl in earnest, causing her to grunt. 

 

Annia was reaching her orgasm when Stasimus stiffened with his own. He stopped his hips and held still inside of her, robbing the girl of her pleasure. 

 

She wrinkled her nose and shook her head as her brother pulled out of her, his cock still as hard as ever thanks to the drugs, “should I do it again?” he wondered as he stared down at his stiff dick. 

 

“I think you should fuck her ass too, don’t you want that?”

 

“Yes, you always say that it’s better than pussy even,” he paused and looked down at Annia’s cunt, “and I like pussy.”

 

“They’re tighter and deeper there. Your mommy loves being fucked in the ass, so I bet your sister will too.”

 

Ada nodded in timid agreement, “but first you have to open her up,” she reminded him

 

“Okay,” he chirped and hopped up to get the lube, pulling it off the side table and pouring some over his fingers eagerly. His mother helped spread the girl’s legs and he quickly began sinking his fingers into Annia’s ass. The girl was used to the treatment and shifted her hips with a murmur. She always had the good feeling when someone was playing with her ass. 

 

Stasimus swirled his fingers around inside of her, making sure to thoroughly coat her walls with lube, “okay, can I fuck her ass now?”

 

He held himself against her, his body taught and excited.

 

“Yes,” said Hart and Stasimus was off, firmly pressing himself into her and groaning as he slipped fully inside. 

 

Annia went very quiet, tears streaming down her red cheeks. And then Stasimus moved his hips. 

 

She wailed.

 

Stasimus didn’t pause, thrusting forward and taking his pleasure from his sister. 

 

His father had been right, Annia’s ass  _ was _ even better then her pussy had been, and he bit his lip as the tight walls gripped him, “fuck,” he breathed out, making his father laugh. 

 

The good feeling was coming back to Annia, the discomfort in her ass fading. The little girl began to squirm underneath her brother and the boy frowned and grabbed her hips, holding her in place as he thrusted. 

 

Ada let go of Annia’s wrists and began to thumb at her little nipples, trying to get the girl to enjoy her rape. She didn’t want this to be a bad experience for the girl, after all. 

 

Annia’s mouth dropped open, “mommy!” she squeaked as her flat chest was played with. Ada shushed her and lightly pinched and rolled her cute nubs, causing her daughter to begin to cry from overstimulation. 

 

Stasimus felt so good inside of her ass, and with her mommy playing with her nipples she began to approach her orgasm, “Oh, Mommy! Mommy, Stasimus is in my ass!”

 

“Does it feel good?” Ada asked her. 

 

“Y-yeeeeah,” Annia sighed and came, her little limbs flailing as she was fucked through her orgasm. 

  
  


Stasimus looked down at his sister and met her teary eyes. That was all it took and the boy came hard, grunting and bucking into her. 

 

The boy’s cock was no longer stiff and it slid free from Annia’s ass, causing them both to murmur and squirm. 

 

Hart gave Stasimus a few slaps on the back as the boy pulled out of his sister, “congratulations, you’ve had your first fucks.” 

 

“It was really good. I wanna do it again,” he looked over at Ada, “and to Mommy too.” 

 

Hart looked at his son fondly before turning his to Ada and meeting her eyes, “of course you can fuck your mommy next.”

 

He watched Ada’s face crumple for a moment before her expression smoothed back out.

 

Ada turned her soft gaze to her son and agreed, “yes, Stasimus, you can fuck me. That would be very nice.”     


End file.
